RESPONSA (Heb. שְׁאֵלוֹת וּתְשׁוּבוֹת; lit. "queries and replies"), a rabbinic term denoting an exchange of letters in which one party consults another on a halakhic matter. Such responsa are already mentioned in the Talmud, which tells of an inquiry touching upon halakhic practice that had been sent to the father of *Samuel (Yev. 105a). It relates of Samuel that he sent to Johanan "13 camels" (some Mss. read גְּוָלִם "parchments" for גְּמָלִים "camels") laden with questions concerning *terefot (Ḥul. 95b). The same passage speaks of a ramified halakhic correspondence that took place between Johanan in Ereẓ Israel and Rav and Samuel in Babylon. Such "letters," of which the amora *Avin wrote many, constituted a general exchange of opinion in halakhah and did not necessarily bear the exact character of "query" and "reply" in the classical sense; they may be considered the inception of the responsa literature. The major novelty lay in the committing of halakhic subjects to writing, the prohibition against committing to writing words transmitted orally (Git. 60b) still being in force at the time. The Talmud (Sanh. 29a) speaks of a litigant who claimed that he could bring a letter from Ereẓ Israel which would support his view, the allusion being to a written "responsum" obtained on presentation of the facts of the case before the respondent in a distant locality.

The Geonic Period

The beginning of responsa literature as a literary and historical phenomenon of important dimensions, however, took place in the middle of the geonic period, when it played a decisive part in the process of disseminating the Oral Law and establishing the Babylonian Talmud as the sole authority in the life of the Jewish people, who were becoming ever more widely dispersed as a result of the Islamic conquests. The Jews of the Diaspora outside Babylon, already strangers to the language and format of the Talmud, turned to the scholars of the Babylonian academies, whom they had always regarded as their spiritual leaders, asking them to send them "such and such a tractate or chapter" together with "its explanation." They also turned to them for decisions on the many disputes which arose continually between different local scholars and on new halakhic problems for which they could find no precedent. Nor were problems wanting on scriptural subjects, traditions, beliefs, and opinions. Accordingly geonic responsa are divisible into: very short responsa, sometimes consisting of only one or two words, such as the earliest surviving responsa, those by *Yehudai Gaon; and responsa containing the exposition of an entire book, chapter, or topic. There was also, understandably, an intermediate group – the most common – of responsa of average scope, but most of these, too, tended toward extreme brevity. The second group mentioned, the "monographic," becomes more prominent toward the end of the geonic period, from *Saadiah Gaon onward, a classical example of this group (not on a halakhic topic) being the Iggeret de-Rav *Sherira Ga'on, written in response to an inquiry by *Jacob b. Nissim of Kairouan.

Of the tens of thousands of geonic responsa, only a small portion has been published in the various collections of geonic responsa. The major portion remains in the Cairo *Genizah fragments and scholars are still engaged in publishing them. More than half the total of the known geonic responsa was written during the last generations of the geonic period, the most prolific writers being Sherira and his son *Hai. During this period of 300 years (750–1050), responsa literature embraced almost every aspect of Jewish life. Apart from issues of practical halakhah, they included explanations of verses and of talmudic themes, theological and ideological discourses, and various chronographic, medical, and scientific discussions, all written at the request of individuals or communities who desired this knowledge, either for the needs of the community or for their polemics with the *Karaites and with their Muslim neighbors. Generally speaking, the queries were assembled by the representatives of the yeshivot from the various Jewish centers of Spain, the countries of North Africa, and those surrounding Ereẓ Israel, to as far as Yemen in the south. These then transmitted them, along with the monetary donation of the communities for the financing and maintenance of the yeshivot, by way of the ramified routes of the postal caravan which passed through Egypt on its way to Babylonia. The representatives, who were usually outstanding scholars, sifted the queries, improved and corrected their language, and as far as possible refrained from answering questions to which answers had already been received on a previous occasion. The answers were copied by the representatives, several copies being preserved in anticipation of similar queries in the future. The yeshivah archives were often drawn upon by later geonim for their own decisions. That a large part of this material has been preserved in the Cairo Genizah is due to the fact that Egypt served as the postal junction of that time.

The yeshivot followed a set procedure for dealing with queries. In general hundreds of such questions were read and discussed at the yeshivah during each of the two months of *kallah in the presence of the full forum of its scholars and pupils. At the conclusion of the discussion the yeshivah scribe wrote the decision of the head of the yeshivah at his dictation, and all the senior members of the yeshivah signed it. Urgent queries which could not be delayed were discussed and decided by the gaon as soon as they were received. In view of the fact that the questioners generally sent groups of queries, sometimes unrelated to one another, the reply of the gaon usually consisted of many sections. The scant mention of previous geonim and their rulings in the responsa stems from a desire to give them the character of impersonal finality, representative of the view of the yeshivah as a whole. The geonic responsa, which in themselves and in their many copies had begun to pile up by their thousands in the different centers of the postal route and outside it, were already collected in early times by various individuals into kovaẓim ("collections") or kunteresim ("booklets"), according to differing criteria: subject matter, the names of the respondents, order of tractates, etc. As a result, responsa which had comprised a single entity when written were divided up by the copyists and attached to different booklets piecemeal. The great number of such secondary booklets and the utter confusion in the names of the respondents, which they carelessly transcribed as a result of the arbitrary order prevailing in them and among their copyists, has rendered the problem of determining the authorship of various responsa one of the most difficult problems in present-day research into geonic responsa. In addition, the habit of most copyists of omitting those opening lines of the questions and answers which had no halakhic significance has increased the problem of identification. Much help is obtained, however, from the lists of responsa (without the responsa themselves) prepared by these copyists for themselves and preserved in the Genizah, in which the opening words of the responsa and the name of the author are noted.

Responsa of the Rishonim

Responsa literature acquired a different character during the period of the *rishonim. Their contents became more and more confined to talmudic halakhah; the responsa became by degrees more and more detailed and lengthy, and the discussion of the parallel talmudic themes, whether closely or distantly related to the topic, grew correspondingly longer and all within the context of a definitive dependence upon the rulings of the geonim which had already become part of binding halakhah, almost like the Talmud itself, especially in the regions of Spain and North Africa. The responsa of the rishonim contain for the first time such expressions of humility as "in my humble opinion," "may the Merciful One save us from the abyss of judgment," and the like, and such admissions as that the understanding of a certain theme, or the determination of a correct reading, "requires further thought." One also encounters for the first time, in the middle of this period, an exchange of responsa between rabbis in different countries, for the purpose of clarifying and reinforcing their rulings and in order to diminish their responsibility in the event of their erring (cf. Hor. 3b). This correspondence also had great value in strengthening the ties between different localities. In contrast to geonic responsa, in which the mention of inter-geonic disputes is very slight (a factor to a certain extent attributable to the insistence of the geonim that their questioners were not to address the same query to more than one yeshivah), the responsa of the rishonim are filled with differences of opinion – another sign of the dwindling authority of the rabbis from the close of the geonic period.

A substantial number of responsa or remnants thereof from the period of the rishonim – some among the earliest – have already been published. Many of the numerous responsa of *Ḥanokh b. Moses and *Moses b. Ḥanokh, of the first generation of Spanish rabbis, for instance, have been published in various collections, especially in the compilation Teshuvot Ge'onei Mizraḥ u-Ma'arav (1888). Some of the responsa of *Gershom b. Judah, "the Light of the Exile," were published by S. Eidelberg (1955). Similarly most of Rashi's extant responsa and remnants of others were collected by I. Elfenbein (1943). Other responsa of the early rishonim of France and Germany were published in the Teshuvot Ḥakhmei Ẓarefat ve-Loter (1881). The situation is different with respect to North Africa, the responsa of whose scholars from the middle of the tenth century and for a considerable time afterward not being preserved in collected form or in great numbers. There are scattered specimens of these, especially in J. Hildesheimer's edition of the Halakhot Gedolot (1886–92) and in various Genizah fragments. The responsa of Isaac *Alfasi (the Rif) are chiefly from his last years in Spain.

The rishonim of France and Germany did not, in general, make collections of their responsa and such collections in our possession represent the work of their pupils and pupils' pupils, who assembled and edited the comprehensive literary legacy of their teachers. This is the case, for example, with the responsa of Jacob *Tam, which were incorporated by his pupils into his Sefer ha-Yashar, together with his novellae, rulings, glosses, etc.; with those of *Eliezer b. Nathan of Mainz; and also, in fact, with the various volumes of responsa which contain the complete literary heritage of *Meir b. Baruch (MaHaRaM) of Rothenburg. In contrast to the geonic responsa, specific collections of the responsa of rishonim have not been collected or arranged. This task was first undertaken by modern scholarship, and the work is still being pursued. The situation was slightly different in the countries of Spain and in the later period in North Africa, where many of the scholars, or their children, or pupils made collections of their responsa. To this can be attributed the large collections of responsa of Solomon b. Abraham *Adret (Rashba) and *Asher b. Jehiel (Rosh or Asheri), among Spanish scholars, and of *Isaac b. Sheshet (Ribash), Simeon b. Ẓemaḥ (Rashbaẓ), and Solomon b. Simeon (Rashbash) *Duran of North Africa, which were well preserved and frequently republished. Of the responsa of other Spanish scholars, however, such as *Naḥmanides (Ramban), Meir *Abulafia (Ramah), *Yom Tov b. Abraham Ishbili (Ritba), and others, only a minute portion has remained, and no additional manuscripts have been discovered.

Only a modicum of the responsa of rishonim has been published in scholarly editions, especially noteworthy among which are the numerous editions of the responsa of Maimonides (Rambam), the most recent and best being that of J. Blau (1957–61); and that of his son, *Abraham b. Moses b. Maimon (by A.H. Freimann, 1937). The fate of the Provençal scholars was completely different. Until very recent years hardly a single book of responsa by one of their outstanding scholars had been published. Only recently have relatively limited collections been published of the responsa of *Abraham b. David of Posquières (Rabad) and Abraham b. Isaac of Narbonne (Rabi [ראב״י]).

Until about the 16th century no self-inspired questions are found in rabbinic literature (with the single exception of the She'iltot of *Aḥa (Aḥai), which was also the first Hebrew book to be composed after the completion of the Talmud). They began to reach respectable proportions, however, in the middle of the 17th century, when the correspondence style became the accepted fashion among maskilim. For an analysis of this phenomenon see below.

Historical Significance of the Responsa

A special importance attaches to responsa as a primary source for knowledge of the history of the Jews in the various countries. Responsa literature has one advantage over such other accepted historical sources as chronographies, official documents, biographies, etc., since the evidence it affords is undesigned, without any specific historical purpose or intention. Moreover, while in general the accepted sources preserve only important events, the responsa echo the humdrum daily life of the ordinary person, his folkways, beliefs, dialects, and, of particular importance, details about the lives of villagers and townsmen whose identity is completely blurred in the usual sources. Since the beginning of modern Jewish *historiography the responsa literature has been drawn upon for this purpose. However, it is only during recent decades that monographs have been devoted both to individual collections of responsa which have been analyzed from the standpoint of their contents as books, and from the point of view of the study of a particular subject. Generally speaking, connected with this research is a study of the biography of the author of the responsa, and as a result, the history of the rabbinate has also benefited. The following works are examples: I. Epstein, The Responsa of Rabbi Solomon ben Adreth of Barcelona… as a Source of the History of Spain (1925); idem, The Responsa of Rabbi Simon ben Ẓemaḥ of Duran as a Source of the History of the Jews of North Africa (1930); A.M. Hershman, Rabbi Isaac ben Sheshet Perfet and his Times (1943); S. Eidelberg, Jewish Life in Austria in the XVth century as Reflected in the Legal Writings of Rabbi Israel Isserlein and his contemporaries (1962). This genre of literature is of additional importance for knowledge of the history of the halakhah, since in it is reflected the first reactions of the halakhic authorities of the various ages to new scientific inventions and discoveries which have increased considerably during recent centuries. It is no longer possible to recognize this immediate reaction of the halakhah in the codes, since the decisions of the respondents underwent many processes of modification and limitation before being summarized in the classical works of the halakhah. In this field a great deal of work was done by Isaak *Kahane, who wrote many monographs on the development of halakhic (but also historical) topics in the responsa literature throughout the ages. (See also *Ma'aseh.)

Boaz Cohen's Kunteres ha-Teshuvot (1930), an annotated bibliography of the rabbinic responsa of the Middle Ages, which was one of the first attemps to classify and describe the responsa literature, became a standard reference work. There was, however, no list of individual responsa scattered in works devoted to other themes. The publication of Shmuel Glick's Kuntress ha-Teshuvot he-Ḥadash: Bibliographic Thesaurus of Responsa Literature Published from ca. 1470-2000, vol. 1: aleph-lamed (2005) is a major contribution toward accessing all types of responsa. In addition to the classic corpus of responsa, the work includes rare responsa found in other works focusing on spheres other than responsa. The Kuntress ha-Teshuvot he-Ḥadash, which has a bibliographical description of over 2,000 books of responsa, provides, among other features, authors' biographical details, a list of the editions of each work and their pagination, the original annotations of Boaz Cohen, and much updated scholarly information.

In 1963 the Institute for Research in Jewish Law attached to the faculty of law and the Institute of Jewish Studies in the Hebrew University of Jerusalem began to index the responsa literature. The index is made up of three parts: the first part gives in great detail all the legal material (Ḥoshen Mishpat and Even ha-Ezer) found in the responsa literature, classified alphabetically according to legal topics in modern scientific terminology; the second part cites all the halakhic sources mentioned in the responsa (from the Bible onward) while the third part gives all the historical material found in the responsa literature, divided according to subjects. Work has started on rishonim literature.

In its final form the project was to analyze the whole of the responsa literature according to a systematic legal index, rendering it possible to find any desired topic discussed in the literature.